Norwegian Singles Method: Subthreshold Running Kept Simple

by James Copeland, Asha Zimmerman MD (Editor), Marius Bakken MD (Foreword)

A middle aged former time trial cyclist shares his experience in the (sometimes miserable) world of running and the methodical system he used to conquer it. This book shows how he went from a 28 minute 5k to 15:01 and a 2:24 debut marathon.

Ideal for time-crunched runners, this guide provides a sustainable pathway to make the most of your training. Includes sample weeks, load management and pacing guidance from the 5k to the marathon with an in-depth look at the theory behind the philosophy.

Foreword provided by Marius Bakken, the first and foremost expert of what became known as the 'Norwegian Double Threshold" system, this book looks to how you can apply these principles to your own running, whilst taking your own busy life and schedule into consideration.

Genres: Nonfiction, Sports

223 pages, Paperback

Published November 28, 2025

Reviews

[Joshua Loong · Rating 4 out of 5]

This is going to be the next new wave of run training. The methodology outlined here is beautiful in its simplicity, but so extremely powerful. And this short, self-published text will be a cornerstone in its history. Future books will be written on this topic, but those of us who have been in it from the start will remember how a simple Letsrun thread eventually took on a life of its own…

As for the book, the methodology is dead simple. Copeland (or sirpoc as most of us know him by) identifies that most runners follow programs that create a boom-bust cycle of training: work really hard for a specific block, followed by a period of lower volume base training. This is a terribly inefficient way to train for most of us since most of the time this leads to burnout, injury etc. that leads to more time off and lower improvement over time.

Inspired by training in cycling and other sports, the most efficient way to train is one in which you can train the most consistently over a longer period of time. This means constructing your training in a way that supports the “sweet spot” of load that improves your performance most efficiently (i.e. accumulate lots of sub-threshold / sub-LT2 work) and fill as much of the rest of your time with aerobic volume (i.e. lots of volume sub-LT1, or more generally, lots of truly, truly, truly easy running).

Doing this with simple workouts and small increases in volume over a long period of time is going to give some extremely amazing results at almost every race distance that is primarily aerobic (the mile to the marathon). Conceptually it’s not something radical, but it’s effectiveness is in its simplicity.

And there’s a lot more in here too. The book is an outline of not just the philosophy itself, but also the specific workouts, pacing strategies, and adaptations for different races and conditions. It’s an amazing resource for getting started on running, and quite literally now the only thing I’d gift anyone that wants a book on run training.

I do have quibbles with the book itself. I give it a bit of a pass since it is self-published and Copeland isn’t a professional writer. The sections adjusting paces for every condition imaginable (wind, elevation, heat etc.) with associated full length tables felt like page count padding. And the structure of chapters and informational delivery was a bit strange and definitely could use some editing (why was half the philosophy embedded just in the background chapter?)

But it’s easy to look beyond it to focus more on the ideas. What’s here is truly something I believe will take over running. I mean, it’s hard not to debate the results, sirpoc himself went from running his first 5k in ~30 mins at the beginning of the pandemic to doing his marathon debut in an absolutely insane 2:24… at 41 years old. It’s that type of legendary running performance that should perk your attention.

So buy the book. Read it. And just get out there and run… 3 x 10 minutes at sub-LT2

[Noah · Rating 4 out of 5]

This is an exceptional training book that any serious hobby runner should read. I’ve been training with James/sirpoc84’s ‘Norwegian Singles Method’ for about 5 months now, and it’s been a game-changer for my motivation and recovery. This book is thoughtfully laid out, cogently written, and backed with extensive scientific studies — all the more impressive for a self-published debut.

[Fernando Remde · Rating 5 out of 5]

In a few years I’ll be able to say I knew about this before it was cool

[Numminummi · Rating 1 out of 5]

Brings nothing new to the table while introducing unnecessary complexity like wind and heat impact on pace…

[Yan Yi · Rating 4 out of 5]

Heard of this method earlier in the year and had spent some time with it, whilst going through the work of reading Reddit and LetsRun. This book is a good consolidation of the idea. I liked the idea, but would really want to have consistent 6 months with it before having any strong opinions.

One thing I learned the most from this book was that my easy runs weren't easier enough; I'm trying to strictly adhere to what the book guides. Considering a newbie to races, the pacing guides were good enough.

That said, my only gripe is that the sidebar/notes sections were way too complex for me to understand today. Hope those sections will click one day for me.

[Ignacio Fernández · Rating 5 out of 5]

Simple pero un libro genial de entrenamiento. Comparto los principios, un gran recurso.

[Gabriel Beltramini · Rating 5 out of 5]

Truly excellent book about running. Every idea is well put together and organized in a way that makes understanding everything super straightforward. What was before the daunting task of going through forum posts, wikis and Reddit, is now a well formatted and very clear book. Anyone interested in running can learn something from this.

[Selmir · Rating 3 out of 5]

I haven't learned anything new from this book, which is disappointing. The author seems genuine, and I find reading about his personal experience and success quite interesting.

However, I don't understand the suggestion to run 3 minutes intervals at 12-15 km pace. For slow runners there may be an argument that their 15 km time is about one hour, which is approximately how long you can run at your threshold pace.
However, for the author that is significantly faster than his projected threshold pace (3:16/km, using VDOT). He is running 3 minute intervals at the pace above LT, so how is this supposed to be a subthreshold method? And does it really differ that much from the standard approach where you, in addition to threshold work, run one VO2 Max session per week?!

Yes, a little slower than the regular approach, but it's too similar to something that existed for decades so I don't see how it warrants writing a book about it and giving that method a new name.

[Kevin Shah · Rating 5 out of 5]

succinct description for the fundamental building blocks of good training

A useful breakdown of a different view for the fundamentals for endurance training.

It is written in accessible prose and with personal stories. The integration of short anecdotes and insets from other contributors (other than Copeland) leads to amusing but but helpful meta references to the genesis of Norwegian singles (eg LetsRun forum).

For the training rationale and physiology descriptions, the apt usage of literature citations were informative but not overbearing.

I hope to incorporate the learnings into my own training!

[Thanawat · Rating 4 out of 5]

Copeland translated and tuned the concept of “Norwegian Double Threshold Training” into actionable “Norwegian Single Threshold Training”. The science part was not that persuasive. The training part was like his own training logs. However, this book provides the most actionable program for NST-integrated marathon plans. Previously, we had Running Formula and Advanced Marathoning. Subthreshold training is going to have its own era.

[timothy m sharp · Rating 4 out of 5]

Well-written, compelling case for run training in a different and more sustainable way. Shame about some slightly iffy graphs.

[Louis Porter · Rating 5 out of 5]

Well written book which summarises and clarifies lots on the NWS method.

[Korey · Rating 5 out of 5]

Cycling training concepts applied to running. Simple, but powerful. He takes it to the Nth degree by factoring in shoes, temperature, wind, elevation, etc. Some good stuff in here.

[Nick Chia · Rating 5 out of 5]

No reason to purchase another training plan or hire a coach for your running after reading this.

[Lisa · Rating 4 out of 5]

a thorough investigation into what might become the next hip running method. ok ok I'll try it for three months!

[Bradley Lund · Rating 5 out of 5]

Great stuff. Clear down to earth and simple.